Expression of estrogen-related receptor beta (ERRβ) in human skin.

Skin is a non classical target tissue for estrogens, whose biological and mechanical properties are affected by the hormonal deprivation occurring at the menopause. Estrogen-related receptors (ERR), closely related to the estrogen receptors (ER), constitute a subfamily of orphan receptors, interfering with ER-mediated signalling pathways. The expression of ERRβ has been detected in only a few adult tissues so far, such as the prostate and the inner ear. Here, we demonstrate the expression of ERRβ in normal human skin. ERRβ was detected in human epidermis, in both keratinocytes and Langerhans cells, by immunohistochemistry. These results were validated on freshly extracted epidermal cells and on monolayer-cultured keratinocytes by RT-PCR and western blotting (WB), suggesting the implication of ERRβ in skin immunity and endocrine effects.